chore: add web_search_tool_type for image support (#13538)

add `web_search_tool_type` on model_info that can be populated from
backend. will be used to filter which models can use `web_search` with
images and which cant.

added small unit test.

codex-rs/core/src/tools/spec.rs

@@ -25,6 +25,7 @@ use codex_protocol::openai_models::ApplyPatchToolType;
 use codex_protocol::openai_models::ConfigShellToolType;
 use codex_protocol::openai_models::InputModality;
 use codex_protocol::openai_models::ModelInfo;
+use codex_protocol::openai_models::WebSearchToolType;
 use codex_protocol::protocol::SessionSource;
 use codex_protocol::protocol::SubAgentSource;
 use serde::Deserialize;
@@ -36,6 +37,7 @@ use std::collections::HashMap;
 
 const SEARCH_TOOL_BM25_DESCRIPTION_TEMPLATE: &str =
     include_str!("../../templates/search_tool/tool_description.md");
+const WEB_SEARCH_CONTENT_TYPES: [&str; 2] = ["text", "image"];
 #[derive(Debug, Clone, Copy, Eq, PartialEq)]
 pub enum ShellCommandBackendConfig {
     Classic,
@@ -49,6 +51,7 @@ pub(crate) struct ToolsConfig {
     pub allow_login_shell: bool,
     pub apply_patch_tool_type: Option<ApplyPatchToolType>,
     pub web_search_mode: Option<WebSearchMode>,
+    pub web_search_tool_type: WebSearchToolType,
     pub image_gen_tool: bool,
     pub agent_roles: BTreeMap<String, AgentRoleConfig>,
     pub search_tool: bool,
@@ -140,6 +143,7 @@ impl ToolsConfig {
             allow_login_shell: true,
             apply_patch_tool_type,
             web_search_mode: *web_search_mode,
+            web_search_tool_type: model_info.web_search_tool_type,
             image_gen_tool: include_image_gen_tool,
             agent_roles: BTreeMap::new(),
             search_tool: include_search_tool,
@@ -1877,18 +1881,27 @@ pub(crate) fn build_specs(
         builder.register_handler("test_sync_tool", test_sync_handler);
     }
 
-    match config.web_search_mode {
-        Some(WebSearchMode::Cached) => {
-            builder.push_spec(ToolSpec::WebSearch {
-                external_web_access: Some(false),
-            });
-        }
-        Some(WebSearchMode::Live) => {
-            builder.push_spec(ToolSpec::WebSearch {
-                external_web_access: Some(true),
-            });
-        }
-        Some(WebSearchMode::Disabled) | None => {}
+    let external_web_access = match config.web_search_mode {
+        Some(WebSearchMode::Cached) => Some(false),
+        Some(WebSearchMode::Live) => Some(true),
+        Some(WebSearchMode::Disabled) | None => None,
+    };
+
+    if let Some(external_web_access) = external_web_access {
+        let search_content_types = match config.web_search_tool_type {
+            WebSearchToolType::Text => None,
+            WebSearchToolType::TextAndImage => Some(
+                WEB_SEARCH_CONTENT_TYPES
+                    .into_iter()
+                    .map(str::to_string)
+                    .collect(),
+            ),
+        };
+
+        builder.push_spec(ToolSpec::WebSearch {
+            external_web_access: Some(external_web_access),
+            search_content_types,
+        });
     }
 
     if config.image_gen_tool {
@@ -2172,6 +2185,7 @@ mod tests {
             create_apply_patch_freeform_tool(),
             ToolSpec::WebSearch {
                 external_web_access: Some(true),
+                search_content_types: None,
             },
             create_view_image_tool(),
         ] {
@@ -2486,6 +2500,7 @@ mod tests {
             tool.spec,
             ToolSpec::WebSearch {
                 external_web_access: Some(false),
+                search_content_types: None,
             }
         );
     }
@@ -2510,6 +2525,38 @@ mod tests {
             tool.spec,
             ToolSpec::WebSearch {
                 external_web_access: Some(true),
+                search_content_types: None,
+            }
+        );
+    }
+
+    #[test]
+    fn web_search_tool_type_text_and_image_sets_search_content_types() {
+        let config = test_config();
+        let mut model_info =
+            ModelsManager::construct_model_info_offline_for_tests("gpt-5-codex", &config);
+        model_info.web_search_tool_type = WebSearchToolType::TextAndImage;
+        let features = Features::with_defaults();
+
+        let tools_config = ToolsConfig::new(&ToolsConfigParams {
+            model_info: &model_info,
+            features: &features,
+            web_search_mode: Some(WebSearchMode::Live),
+            session_source: SessionSource::Cli,
+        });
+        let (tools, _) = build_specs(&tools_config, None, None, &[]).build();
+
+        let tool = find_tool(&tools, "web_search");
+        assert_eq!(
+            tool.spec,
+            ToolSpec::WebSearch {
+                external_web_access: Some(true),
+                search_content_types: Some(
+                    WEB_SEARCH_CONTENT_TYPES
+                        .into_iter()
+                        .map(str::to_string)
+                        .collect()
+                ),
             }
         );
     }